This specification includes a computer program listing appendix consisting of Appendices A, B, C and D, which are stored on CD-ROM as the following files, respectively: Appendix_A.txt (13.4 Kbytes), Appendix_B.txt (17.2 Kbytes), Appendix_C.txt (8.16 Kbytes), and Appendix_D.txt (15.2 Kbytes), all created on Aug. 22, 2001. These files, which are incorporated herein by reference, contain a partial source code listing of one aspect of a preferred embodiment of the invention. The copyright owner has no objection to the reproduction of this code listing as part of this patent document, but reserves all other copyrights whatsoever.
The present invention relates to the field of search engines. More specifically, the invention relates to techniques for facilitating viewing search results that span multiple item categories, and for locating web pages that include offerings for products and other types of items.
In the field of electronic commerce, it is common for online merchants to sell products within many different product-related categories. For example, Amazon.com, Inc., the assignee of the present application, sells products within the categories of books, music, video and DVD, toys and games, electronics, home improvement, and auctions. The predefined categories and associated products are typically presented to users in the form of a browse tree. In addition, many merchants provide a search engine for conducting searches for products.
One problem, commonly encountered by online merchants is the inability to effectively present groups of related products that span the predefined categories. Due to the large number of products and categories, and the organization of the web site, many relationships between products may be difficult for the user to ascertain. For example, suppose a user of a merchant""s web site is a fan of the American humorist and author Mark Twain. The user may choose to look for books written by Mark Twain through a browse tree in the book section of an on-line commerce web site. Browsing in this manner is likely to reveal a large number of books authored by, or written about, Mark Twain. The user, however, may be unaware that the web site also sells products other than books that may be of interest to fans of Mark Twain. For example, a videos section of the same web site may contain video biographies of Mark Twain and video adaptations of many of his classic books, while a music section may include compact discs with songs inspired by his writings. Similarly, an auctions section of the same site may contain products offered for sale by third parties that may be of interest to the user, such as Mark Twain memorabilia. Although use of the web site""s search engine may reveal some of these additional products, the user typically must review a long list of search results in order to identify the products or categories of interest.
Another problem in the field of on-line commerce is that of locating a web site from which a particular product can be purchased. This problem may arise, for example, when the online merchants known to the consumer do not carry the product of interest. In such a circumstance the consumer may use an Internet search engine such as ALTAVISTA or EXCITE to search for a web site that sells the product. The scope of such a general search is often large enough, however, that only a small fraction of a large number of located web sites actually offer the product for sale. For example, the search may include a relatively large number of sites that merely provide reviews, technical support, specifications, or other information about the product of interest. Thus the sites of greatest interest to the consumer are likely to be buried deep within a long list.
The present invention seeks to overcome these and other problems.
The present invention provides various features for assisting users in conducting online searches. The features may be embodied alone or in combination within a search engine of an online merchant, an Internet search engine, or another type of search system.
One feature of the invention involves a method for displaying the results of a multiple-category search according to levels of significance of the categories to a user""s search query. The method can be used to display the results of a search for products or for any other type of item. In a preferred embodiment, the method involves receiving a search query from a user and identifying, within each of multiple item categories, a set of items that satisfy the query. The sets of items are then used to generate, for each of the multiple categories, a score that indicates a level significance or relevance of the category to the search. The scores may be based, for example, on the number of hits (items satisfying the query) within each category relative to the total number of items in that category, the popularity levels of items that satisfy the query, or a combination thereof.
The categories and associated items are then presented to the user in a display order that depends upon the scoresxe2x80x94preferably from highest-to-lowest significance. Other significance criteria, such as a category preference profile of the user, may additionally be used to select the display order. In addition, other display methods for highlighting the most highly ranked categories may additionally or alternatively be used. The method increases the likelihood that the categories that are of most interest to the user will be presented near the top of the search results listing, or otherwise called to the attention of the user. To assist the user in efficiently viewing a cross section of the located items and their categories, no more that N items (e.g., the most highly ranked three items) within each category are preferably displayed on the initial search results page.
Another feature of the invention involves a system and methods for assisting users in locating web sites or pages from which user-specified products can be purchased. In a preferred embodiment, each web page located by a crawler program is initially evaluated, according to a set of content-based rules, to generate a score that indicates a likelihood that the web page includes a product offering. The scores may additionally be based on other criteria, such as the content of other web pages of the same web site. Representations of some or all of the scored web pages are stored in a keyword index that maps keywords to addresses (URLs) of the web pages. The keyword index is used by a query server to locate web pages that are both relevant to a user""s search query and likely to include a product offering. This may be accomplished, for example, by limiting a scope of the search to web pages having a score that satisfies a particular threshold.
In one embodiment, the above-described features are embodied in combination within a search engine of a host merchant""s web site. From this web site, a user can initiate an xe2x80x9cAll Productsxe2x80x9d type search that spans multiple product categories. The submitted search query is used to identify a set of products that satisfy the query, and a set of web pages that both satisfy the query and that have been determined to likely include product offerings. The results of the search are presented using a composite web page which lists at least some of the located products and at least some of the located web pages. The products are preferably displayed in conjunction with their respective product categories according to the above-described category ranking and display method.